To get information out, Hogan makes use of an American actor that is appearing in a German propaganda film.
Did You Know?
Entertainers were part of the Army Special Services who had a motto of "Entertainment for the Soldier, by the Soldier". All the ranks were enlisted, so Buckles would have been enlisted although his characters may be officers so Hogan should not have referred to him as major. Many famous actors have been part of this service which began in 1774 and was reformed in 1940 for the war. See more
Right after Hogan and Klink go back to Klink's guests in his quarters, and you see the previous goof where Klink does not have his monocle, the Major stands up to talk to Klink and Hogan. He is holding a glass in his left hand. When the camera changes angle and you notice Klink now has his monocle again, the Major is holding his glass in his right hand. See more
Major Byron Buckles
If I'm going to die, at least let it be in a close-up.